The broad, long-term objective is to increase our understanding of the extent of sterility and the causes of sterility in sub-Saharan Africa. The analysis will determine the level, age pattern and trend of sterility, the geographic distribution, as well as the socioeconomic, cultural and demographic differentials of incidence and prevalence of sterility. The countries to be studies are the following: Benin, Botswana, Burundi, Cameroon, Ghana, Ivory Coast, Kenya, Lesotho, Liberia, Mali, Mauritania, Nigeria, Senegal, Sudan, Togo, Uganda, and Zimbabwe. Two specific aims flow from this objective: Aim 1: Population Estimates of Sterility: To determine the magnitude of contraception that has a negligible impact on population estimates of the level and age pattern of sterility using a microsimulation study. The biasing effect of contraception will be analyzed in several parts as follows: 1) the degree of contraceptive efficacy; 2) duration of contraceptive use; and 3) proportion of women using contraception. In an empirical analysis of all WFS and DHS surveys for sub-Saharan Africa the level, age pattern and trend of sterility by country, by region and by ethnic group will be estimated. The impact of a decline in sterility on fertility will be assessed. Aim 2: Individual Estimates of Sterility: To determine the magnitude of contraception that has a negligible impact on individual estimates of sterility, i.e. on assignment of age at onset of sterility to the individual woman, and estimates of incidence and prevalence of sterility using a microsimulation study. The biasing effect of contraception will be analyzed in several parts as follows: 1) the degree of contraceptive efficacy; 2) duration of contraceptive use; and 3) proportion of women using contraception. In an empirical analysis we will estimate socioeconomic, cultural and demographic differentials of incidence and prevalence of sterility within each country. Based on the results of this multivariate analysis inferences as to the relationship between sterility and women's status will be made, and public health policies to prevent and treat sterility at a young age will be discussed.